9 September 2016, The Conversation, EcoCheck: the Grampians are struggling with drought and deluge. Our EcoCheck series takes the pulse of some of Australia’s most important ecosystems to find out if they’re in good health or on the wane. The Grampians National Park is a large conservation reserve, sprawling across 168,000 hectares embedded in western Victoria’s agricultural landscape. With a rich cultural heritage and regionally important flora and fauna, it is a hugely significant area for conservation. But in recent years it has been subjected to a series of major wildfire events, a flood, and long periods of low rainfall. Our research shows that this has sent small mammal populations on the kind of boom-and-bust rollercoaster ride usually seen in arid places, not temperate forests.The fire and the flood We began studying the Grampians in 2008, investigating how small mammals had responded to a catastrophic wildfire that burned half of the national park in 2006. What started as a one-year study has turned into a long-term research program to investigate how the past few years of hypervariable rainfall and heightened bushfire activity have affected the animals that live in the park. Fortunately (for our study, at least), the beginning of our research in 2008 was in the middle of a long run of very poor rainfall years, as the Millennium Drought reached its height. The drought was broken at the end of 2010 by the Big Wet, which led to well-above-average rainfall and floods in the Grampians. But soon after, rainfall rapidly dipped back to below average. It has stayed there ever since. We also saw two more major fire events, in 2013 and 2014, which together with the 2006 fire burned some 90% of the Grampians landscape. Read More here
Tag Archives: forest response
5 September 2016, DESMOG, Climate Impacts: Melting Glaciers, Shifting Biomes and Dying Trees in US National Parks. Trees are dying across Yosemite and Yellowstone national parks. Glaciers are melting in Glacier Bay National Park and Preserve in Alaska. Corals are bleaching in Virgin Islands National Park. Published field research conducted in U.S. national parks has detected these changes and shown that human climate change – carbon pollution from our power plants, cars and other human activities – is the cause. As principal climate change scientist of the U.S. National Park Service, I conduct research on how climate change has already altered the national parks and could further change them in the future. I also analyze how ecosystems in the national parks can naturally reduce climate change by storing carbon. I then help national park staff to use the scientific results to adjust management actions for potential future conditions. Research in U.S. national parks contributes in important ways to global scientific understanding of climate change. National parks are unique places where it is easier to tell if human climate change is the main cause of changes that we observe in the field, because many parks have been protected from urbanization, timber harvesting, grazing and other non climate factors. The results of this research highlight how urgently we need to reduce carbon pollution to protect the future of the national parks. Melting Glaciers, Dying Trees Human-caused climate change has altered landscapes, water, plants and animals in our national parks. Research in the parks has used two scientific procedures to show that this is occurring: detection and attribution. Detection is the finding of statistically significant changes over time. Attribution is the analysis of the different causes of the changes. Around the world and in U.S. national parks, snow and ice are melting. Glaciers in numerous national parks have contributed to the global database of 168 000 glaciers that the Intergovernmental Panel on Climate Change (IPCC) has used to show that human climate change is melting glaciers. Field measurements and repeat photography show that Muir Glacier in Glacier Bay National Park and Preserve in Alaska lost 640 meters to melting from 1948 to 2000. Read More here
5 September 2016, CSIRO ECOS, Wired woodlands signal stress as climate dries. In 2015, the normal ‘breathing’ pattern of the Great Western Woodlands in south-western Australia became erratic. In response to lack of rain, the old-growth woodland started to ‘breathe in’ oxygen and ‘breathe out’ carbon dioxide – the opposite of what occurs in normal plant photosynthesis, and a sign the trees were ailing. Lift your eyes above the orange- and gold-hued gimlets and salmon gums that characterise these woodlands and you can see the key to understanding this reversal of nature; a 36m tower equipped with highly sensitive instrumentation.It’s the technology in that tower that has been tracking the trees’ struggle for survival; collecting data on the activity of the woodland by the second and updating daily CSIRO researchers based in Perth. The tower, run by CSIRO researchers Dr Suzanne Prober and Dr Craig Macfarlane, is a part of Australia’sTerrestrial Ecosystem Research Network (TERN) OzFlux Facility. A series of 24 OzFlux towers and 10 associated Supersites have been established as sentinels of change across the country. Toward the TERN goal of creating a national ecosystem observatory, each monitors changes in carbon, water and biodiversity in a nationally significant landscape. Read More here
29 June 2016, NASA, NASA maps California drought effects on Sierra trees. A new map created with measurements from an airborne instrument developed by NASA’s Jet Propulsion Laboratory, Pasadena, California, reveals the devastating effect of California’s ongoing drought on Sierra Nevada conifer forests. The map will be used to help the U.S. Forest Service assess and respond to the impacts of increased tree mortality caused by the drought, particularly where wildlands meet urban areas within the Sierra National Forest. After several years of extreme drought, the highly stressed conifers (trees that produce cones and are usually green year-round) of the Sierra Nevada are now more susceptible to bark beetles (Dendroctonus spp.). While bark beetles killing trees in the Sierra Nevada is a natural phenomenon, the scale of mortality in the last couple of years is far greater than previously observed. The U.S. Forest Service is using recent airborne spectroscopic measurements from NASA’s Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) instrument aboard NASA’s ER-2 aircraft, together with new advanced algorithms, to quantify this impact over this large region of rugged terrain. The high-altitude ER-2 aircraft is based at NASA’s Armstrong Flight Research Center, Edwards, California. Read More here